Furnace



Oct. 6, 1931. D. L. SUIVIMEY FURNAC E Filed Feb. 5. 1929 2 Sheets-Sheet l IINV%TOR' L; l rj Cb HI ATTORNEYS.

Patented Oct. 6, 1931 UNITED STATES PATENT OFFICE DAVID L. SUMMEY, OF WATERBURY, CONNECTICUT, ASSIGNOR TO SCOVILL MANUFAC- TUBING- COMPANY, OF WATERBURY, CONNECTICUT, A CORPORATION OF CON- N ECTICUT FURNACE Application filed February 5, 1929. Serial No. 337,569.

This invention relates to furnaces and to processes for heat treatment of materials therein.

It is an object of the invention to provide a furnace for heat-treating materials such that the waste heat freed during the cooling of a treated charge is utilized to preheat a cold or fresh charge.

It is a further object of the invention to provide a furnace in which the charges may be handled in a simple and economical manner.

invention consists in the features, combinations, details of construction and arrange ments of parts which will first be described in connection with the accompanying drawings and then more particularly pointed out.

In the drawings:

Figure 1 is a diagrammatic sectional View of a furnace constructed in accordance with the invention;

Figure 2 is a detail plan view of part of the conveyor mechanism; and

. Figures 3 to 7 are diagrams illustrating the progressive positions of the parts.

Referring to the drawings, the furnace illustrated is designed particularly for annealing coiled strips of brass or copper, but it is to be understood that the invention may be used for other metals and other heat treatments. The furnace shown comprises a housing 5 enclosing a heating chamber 6 and a preheating chamber 7. Between the two chambers is a partition 8 having an opening 9 connecting the chambers. This opening is normally closed by a swinging door 10. A similar door 11 normally closes an opening 12 formed in the end wall of the furnace and leading into the preheating chamber.

The heating chamber 6 is provided with heating means such, for instance, as electric resistors diagrammatically indicated at 13. Supplemental resistors 1311 may be used in the preheating chamber. if desired. The resistors serve to carefully regulate the temperatures in the chambers during the process, so that the heat treatment is regulated and carried out successfully. 7

There is provided a member in the prev f 16 and a lower deck 17. With these and other objects in view, the

heating chamber serving as a common support for a hot chargebeing heated and a cold charge being preheated. This member either deck into alinement with the opening 9 between the two chambers. In the preferred embodiment shown, the preheating chamber 7, is provided with a slidably mounted elevator frame 15 having an upper deck On the lower side of the frame are racks 14 meshing with pinions 19 on a shaft 20. This shaft is rotated, to raise or lower the elevator frame, by means of a gear 21 to which power may be applied in any suitable manner.

When the elevator is in the position of Figure 1, deck 17 is so positioned that a charge carried thereby is in alinement with opening 9 leading to the heating ghamber.

By lowering the elevator, deck 16 is brought into alinement with the opening. In the heating chamber is a support 18 for the charge under treatment, which is level with the alined deck of the elevator. Also, on this level and outside the furnace, is a support 22, for receiving a discharged treated charge and positioning a cold charge for insertion.

In the position of Figure 1, a charge, indicated by B, is in the heating chamber being treated. The elevator supports a.previously heated charge A on the upper deck 16 and a cold charge C on lower deck 17 Thus, while charge B is under heat treatment, cold charge C is being preheated by the waste heat given ofl:' from charge A while the latter is cooling.

There is provided means for moving charges into and out of the two chambers of the furnace and in structures embodying the invention to what is now considered the best advantage, the two horizontally alined charges are moved simultaneously. This may be accomplished by means of a conveyor movable over the decks and supports and having links vertically separable from the conveyor to accommodate the vertical movement of the elevator. Although capable of various constructions, in that here illustrated as an example. an endless conveyor 25'runs through the furnace, passing over pulleys or sprockets 26 outside the furnace. The conveyor is moved by applying power to any of these pulleys in any suitable manner.

The three charges in the furnace are directly carried by trays and these trays are interchangeable, so that any two of them may be made links in the endless conveyor. In the position of Figure 1, the cooling charge A is carried on tray 27, hot charge B on tray 28, and cold or fresh charge C on tray 29.

Each tray is preferably fiat on the underside to be slidable conveniently on the decks and supports. On the upper side the trays may be formed to suit the type of material,

under treatment. The trays here shown are flat to receive coils of metal.

The trays are preferably adapted for detachable and interchangeable locking engagement in the conveyor. To this end, each tray may have at one end a T-shaped connecting tongue 31 and at the other end a socket-forming lug 32 having a socket corresponding to the T-head of the tongue. The T-head of one tray, when inserted in the socket of the adjacent tray, forms a hook connection such that either tray will draw the other. That is, the trays are interlocked and are connected for simultaneous horizontal movement in either direction. To connect the trays in the conveyor, the tongue of one tray hooks into a socket-lug 33, like lug 32, on a conveyor link 34 and the socket of the other tray receives a T-headed tongue 35, like tongue 31, formed as part of the conveyor. In this position (Figure 2) the trays are, in effect, links in the endless conveyor.

The T-heads are vertically slidable in their sockets so that a tray may be separated from or inserted in the conveyor as' the elevator moves.

The steps in the process of heat treatment in the improved furnace are illustrated diagrammatically in Figures 3 to 7 inclusive where Figure 3 illustrates the same position of parts as in Figure 1. After the heat treatment of charge B is completed, the elevator is lowered to down position. During this movement, tray 29 carrying'the fresh charge rides out of the conveyor line and tray 27 carrying the cooled and treated charge takes its place, the tongue and socket of tray 27 automatically connecting up with the socket of the conveyor and the tongue of the other tray. This position is indicated in Fig. 4.

The conveyor is now moved (to the right as shown in the drawings) a distance approximately equal to the length of one tray. This discharges tray 27 with treated charge A out of the furnace onto support 22 and withdraws tray 28 with its hot charge B into the preheating chamber, as shown in Figure 5. Charge A is then removed in any suitable manner.

To place preheated charge C in line with the heating chamber, the elevator is raised to up position. Tray 28 thereby rides out of the conveyor and tray 29 takes its place. A new cold charge D is supplied in any suitable manner to tray 27 outside the furnace. This position is shown in Figure 6.

Ihe conveyor is then given a reverse movement which transfers tray 29 with its preheated charge G into the heating chamber and simultaneously inserts cold charge D into the preheating chamber. In this position (Figure 7) charge D is preheated by the waste heat from charge B while charge C is being heated.

This cycle of steps is repeated for each new charge, the interchangeable trays progressing through the various positions and reaching their original relative positions every three cycles.

It will be understood that the process and apparatus herein described are capable of numerous variations and alterations in practice. There is shown an elevator for shifting the charges to the conveyor in the preheating chamber, but other forms of mechanisms might be utilized instead.

What I claim is:

1. A furnace comprising means forming a heating chamber and a preheating chamber communicating therewith, heating means for said heating chamber, charge handling mechanism including vertically movable elements cooperating therewith for extracting a cooled treated charge from the preheating chamber, conveying a heated charge from the heating chamber to the preheating chamber and a preheated charge from the preheating chamber to the heating chamber, and adding a fresh charge to the preheating chamber.

2.. A furnace comprising means forming a heating chamber and a preheating chamber communicating therewith, heating means in the heating chamber, a conveyor common to the two chambers, interchangeable trays having detachable locking engagements in the conveyor and forming parts thereof, and a movable member in the preheating chamber for interchanging the trays in predetermined I preheating chamber for moving a charge into and out of alinement with said door,

4. In combination, a furnace comprising a heating chamber and a preheating chamber in communication therewith, conveyor means movable horizontally through the furnace and comprising a plurality of interengaging interchangeable trays for carrying the charges to be treated, said trays being free to have individual vertical movement, an additional interchangeable tray, and an elevator having two decks in superimposed relation for bearing said trays and movable in the preheating chamber to place the tray carried by either deck in'ho'rizontal alinement with the conveyor means and at the same time to remove another tray from the conveyor. 4

5. In combination, a furnace comprising a heating chamber and a preheating chamber in communication therewith, the preheating chamber having a charging and discharging door, a pluralityof interchangeable trays engageable with one another for carrying the. charges to be heated, and tray moving mechanism for shifting the trays successively through a cycle in-which the tray is moved, by successive steps, into the preheating chamber, into the heating chamber, back into the preheating chamber and out of the furnace.

6. In combination, a furnace comprising a heating chamber and a preheating chamber in communication therewith, the preheatingchamber having a charging and discharging door, a plurality of interchangeable trays engageable with one another for carrying the vcharges to be heated, and tray moving mecha-' nism for shifting each tray successively through a cycle comprising, '(a) movement into the preheating chamber, (1)) movement in the latter to an offset position, (a) return to former position, (at) transfer into the heating chamber, (6) return to' the preheating chamber, (f) movement in the latter to an J oflset position, (g return'to former position, (it) and removal rom the furnace.

7. In combination, a furnace comprising a heating chamber and a preheating chamber in three interchan eable trays, any two of which serve as part 0 the conveyor, each tray having a tongue and a socket at opposite ends thereof, one of said conveyor elements having a similar tongue, the other having a similar socket, said tongues and sockets being arranged to interlock the trays in the conveyor for horizontal conveyor movement but permitting free vertical movement of the individual trays, and means movable vertically in the preheating chamber for removing one tray from the conveyor and substituting another tray. I

In testimony whereof, I have hereunto set m hand. y DAVID L. SUMMEY.

communication therewith, spaced conveyor elements forming part of a conveyor movable in the furnace, three interchangeable trays any two of which serve as part of said conveyor, interlocking elements on said trays and on said conveyor elements whereby the trays in line with said conveyor elements are interlocked in the conveyor but are free to have independent vertical movement, and means vertically movable in the preheating chamber for removing one tray from the conveyor and substituting another tray;

8. In combination, a furnace comprising a heating chamber and a preheatin chamber in communication therewith, space conveyor elements forming part of a conveyor movable in opposite directions in the furnace, 

